共查询到17条相似文献，搜索用时 281 毫秒
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试验取 1、30、15 0日龄三组健康皖西白鹅的消化管各段 ,制作组织切片 ,观察雏鹅、仔鹅和成体鹅的食管、腺胃、小肠各段、盲肠、直肠及卵黄囊憩室管壁内淋巴组织分布特点。见各段粘膜及粘膜下层内均存在不同类型的淋巴组织 ,其中食管、空肠、回肠、盲肠及卵黄囊憩室壁内分布的淋巴组织尤为发达 ,表明皖西白鹅消化管的局部免疫功能很强 ,其有较强的抗病力。 相似文献
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本试验研究了皖西白鹅呼吸器官的形态特征.试验选用成年皖西白鹅20只,通过颈动脉放血致死后,用10%福尔马林溶液固定.采用肉眼和显微镜观察皖西白鹅呼吸器官的形态位置与结构特征.结果表明成年皖西白鹅的呼吸器官由鼻腔、喉、气管、鸣管、支气管、气囊和肺等组成. 相似文献
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本试验研究了皖西白鹅呼吸器官的形态特征。试验选用成年皖西白鹅20只，通过颈动脉放血致死后，用10%福尔马林溶液固定。采用肉眼和显微镜观察皖西白鹅呼吸器官的形态位置与结构特征。结果表明成年皖西白鹅的呼吸器官由鼻腔、喉、气管、鸣管、支气管、气囊和肺等组成。 相似文献
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目的:研究能量蛋白水平对皖西白鹅种鹅繁殖性能和血清生化指标影响.方法:试验分别设3个蛋白水平(15％、16％ 和17％)和两个能量水平(10.67 MJ/kg和11.09 MJ/kg).选取24月龄皖西白鹅种鹅360只,随机分成6组,每组均设6个重复,每个重复10只(公母比1:4).其中试验Ⅰ、Ⅱ和Ⅲ组能量蛋白水平分别为10.67 MJ/kg(15％、16％ 和17％);试验Ⅳ、Ⅴ和Ⅵ组分别为11.09 MJ/kg(15％、16％ 和17％).试验期7周,检测分析比较各组间指标的差异.结果:不同饲粮能蛋比对皖西白鹅种鹅产蛋期精料采食量、产蛋枚数、蛋重和平均蛋重无显著差异(P>0.05);试验Ⅰ组和试验Ⅱ、Ⅲ、Ⅴ、Ⅵ组的破蛋率差异显著(P<0.05).日粮中能量蛋白水平不同时,试验各组皖西白鹅种鹅血清中TC、TG、UA、葡萄糖、HDL-C、LDL-C、Ca的含量无显著差异(P>0.05);血清中TP、GLOB、A/G含量试验Ⅴ组和试验Ⅱ组差异显著(P<0.05);血清中ALP含量试验Ⅵ组和试验Ⅰ组差异显著(P<0.05);血清中尿素含量试验Ⅱ组和试验Ⅰ组差异显著(P<0.05);血清中P含量试验Ⅴ组和试验Ⅰ、Ⅱ、Ⅲ、Ⅵ组差异显著(P<0.05).日粮中不同能量蛋白水平对皖西白鹅种蛋入孵数、无精蛋和孵化率无显著影响(P>0.05);试验Ⅵ组与试验Ⅱ组受精率差异显著(P<0.05);试验Ⅲ组的死胚蛋与试验Ⅳ、Ⅴ、Ⅵ组差异显著(P<0.05).结论:日粮中不同能量和蛋白质水平对皖西白鹅种鹅产蛋性能和种蛋孵化性能有影响.能量水平为10.69 MJ/kg,粗蛋白质水平为16％ 时种蛋受精率和孵化率最佳. 相似文献
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Kalwant Bhopal 《British Journal of Sociology of Education》2020,41(6):807-816
AbstractThis article explores how White privilege and a hierarchy of oppression have resulted in competing identities in which gender has been given greater importance compared to race. I argue that the sociology of education needs to adopt an intersectional approach that travels in different directions if it is to remain valid. The article examines how gender, perpetuated by White privilege, continues to play a key role in the positioning of Black and minority ethnic staff, students and pupils within a range of stereotypes that operate to marginalise their life trajectories. The article argues that if sociologists of education are unwilling to challenge White privileged populist discourses and their own positions of White privilege, then they will become complicit in maintaining a socially unjust status quo. 相似文献
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David Gillborn Sean Demack Nicola Rollock Paul Warmington 《British Educational Research Journal》2017,43(5):848-874
Drawing on a secondary analysis of official statistics, this paper examines the changing scale of the inequality of achievement between White students and their Black British peers who identify their family heritage as Black Caribbean. We examine a 25‐year period from the introduction of the General Certificate of Secondary Education (GCSE), in 1988, to the 20th anniversary of the murder of Stephen Lawrence in 2013. It is the first time that the Black/White gap has been analysed over such a long period. The paper reviews the changing place of the Black/White gap in education debates and notes that, despite periods when race equality has appeared to be high on the political agenda, it has never held a consistent place at the heart of policy. Our findings shed light on how the Black/White gap is directly affected, often in negative ways, by changes in education policy. Specifically, whenever the key benchmark for achievement has been redefined, it has had the effect of restoring historic levels of race inequity; in essence, policy interventions to ‘raise the bar’ by toughening the benchmark have actively widened gaps and served to maintain Black disadvantage. Throughout the entire 25‐year period, White students were always at least one and a half times more likely to attain the dominant benchmark than their Black peers. Our findings highlight the need for a sustained and explicit focus on race inequity in education policy. To date, the negative impacts of policy changes have been much more certain and predictable than occasional attempts to reduce race inequality. 相似文献
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林开强 《楚雄师范学院学报》2003,18(5):50-52
西南少数民族的白石崇拜非常突出。本文以雪山——男精——雪山之精——白石——男性祖先石神——妇女宜子作为分析线索，力图给白石崇拜以合理的解释。认为西南少数民族的白石崇拜实质就是生殖崇拜的表现形式，白石即是男精之象征。 相似文献
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Mary E. Hess 《Religious education (Chicago, Ill.)》2017,112(1):46-57
AbstractDecades of work in dismantling racism have not yielded the kind of results for which religious educators have hoped. One primary reason has been what scholars term “white fragility,” a symptom of the structural racism which confers systemic privilege upon White people. Lessons learned from Christian mystics point to powerful ways to confront and resist the siren call of such formation and instead to make resisting racism an integral part of Christian identity for White people. 相似文献
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Zero tolerance school discipline practices have been associated with a national increase in suspensions, a practice that has had a disproportionate negative impact on Black students. The present study investigated an association between principal attitudes toward zero tolerance and suspension rates for White and Black students in 306 Virginia high schools. Black suspension rates were more than double White suspension rates. Regression analyses controlling for student poverty and school enrollment showed that principal endorsement of zero tolerance was moderately associated with suspension rates for both White and Black students, but was not associated with the size of the racial disparity. Paired‐samples t tests showed statistically significant differences in the types of offenses that resulted in suspensions, with Black students significantly more likely to be suspended for disruptive offenses and White students more likely to be suspended for alcohol‐ and drug‐related offenses. 相似文献
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Kitae Sohn 《The Urban Review》2011,43(2):217-234
The hypothesis of acting White has been heatedly debated and influential over the last 20 years or so in explaining the Black–White
test score gap. Recently, economists have joined the debate and started providing new theoretical and empirical analyses of
the phenomenon. This paper critically reviews the arguments that have been advanced to support and refute the hypothesis.
This review particularly covers the analyses in economics because the economic analyses are relatively new and usually neglected
in other disciplines. Also, nationally representative data are emphasized, whenever possible, to improve the generalizability
of the arguments. This review concludes that although the analyses in both non-economics and economics are thought-provoking
and compelling in some respect, a substantial body of empirical evidence is inconsistent with the assumptions of and results
from the analyses. 相似文献
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This article critically analyzes the narratives of 62 White male undergraduates at a single institution about their views on race and experiences with racism. It is framed by Mills' (1997) conception of Whiteness that is founded upon an inverted epistemology or an epistemology of ignorance. Therefore, this analysis centers the ways in which White male undergraduates concurrently downplay the contemporary significance of White privilege while examining the role college experiences have at reinforcing this structured ignorance. The themes from their interviews included: (1) White ignorance and White identity as meaningless; (2) Evasive White racial ignorance; and (3) Racial arrested development and racial regression. These findings emphasize the need to creatively challenge White males to develop their racial selves, especially because their ignorance fuels the linguistic and physical violence Students of Color regularly experience. 相似文献